How does The Master shrink people? Doctor Who's Tissue Compression Eliminator explained

Yes, Spyfall - Part One closed with the dramatic return of the Master (Sacha Dhawan), but almost as significant for fans will be the return of his trademark weapon, the Tissue Compression Eliminator – or 'TCE' for short.

The TCE has been a part of the Master's arsenal ever since he first appeared (then played by Roger Delgado) in 1971's Terror of the Autons and remained his primary sidearm throughout the 1980s.

A matter-compressing weapon, the TCE kills by shrinking the bodies of its targets to the point where their life functions cease.

Though it was capable of shrinking victims down to microscopic size, the deranged Master would often reduce his prey to a doll-like scale and leave their tiny corpses as a calling-card for the Doctor to find.

Though a popular gimmick with fans, the TCE was dispensed with when the Master returned to Doctor Who in the post-2005 revived series – John Simm's incarnation used a 'laser screwdriver' which mimicked the Doctor's own sonic device, while Missy (Michelle Gomez) used a vaporising energy weapon in the 2014 episode 'Dark Water'.

But with Spyfall - Part One, the Tissue Compression Eliminator is back – though we don't actually see it in use, the Master reveals that he'd ambushed the Doctor’s old ally 'O' and taken his form, shrinking the real 'O' and placing his corpse inside a matchbox for safe-keeping. Brrrr...

The resurrected Master certainly looks set to cause big problems for the Doctor (Jodie Whittaker) and friends when Spyfall continues this Sunday (5th January) on BBC One.